1. Field of the Invention
This invention relates to a security system, and more particularly, to a security system capable of having its functions wirelessly programmed without removing any of its components from a vehicle.
2. Background Art
Security systems are widely deployed for passenger vehicles, such as family sedans and vans, which represent valuable possessions for ordinary families and small businesses. A typical vehicle security system is incorporated as part of the electronic system of a vehicle and provides a selection of security functions such as intrusion alarm arming and automatic door locking. It can also serve as a user convenience system to aid in the location of a vehicle located in a crowded parking lot.
Vehicle security systems are generally classified as being either active arming or passive arming systems. In the passive arming category, there are systems with or without a door-locking function, systems with or without an arming/disarming chirp, and so on. Similar functional varieties can also be found for active arming systems. Whatever the category, it is desirable to construct the system in a way that allows the functions of the vehicle security system to be programmable by the user. A user of a vehicle security system living in an apartment, for example, may want to turn off the arming/disarming chirp, or reduce the sound level of the chirp if he frequently comes home late. The sensitivity of the intrusion alarming function may also need to be adjusted to prevent false alarms on windy days.
As a self-contained electronic system, it is desirable for a vehicle security system to be configured to conform to user decisions about which of the provided security functions should be enabled or disabled. System configuration also includes setting adjustable features, such as the chirp sound level mentioned above, which are set to levels suitable for the environment in which these systems operate. Thus, when attempting to set up, or program, the functions of a vehicle security system, the design of the interface between the security device and the user becomes important in providing a convenient, successful and efficient security device.
For the purpose of describing the invention, several prior-art vehicle security systems are briefly examined in the following paragraphs with reference to the accompanying drawings. Among the examined security systems, FIG. 1 is a block diagram illustrating the circuit configuration of a conventional system that employs a dual in-line package (DIP) switch array for programming the security functions. The systems of FIGS. 2 and 3 have basically the same circuit configuration, although they employ different function-programming methodologies.
FIG. 1 illustrates a conventional vehicle security system. It includes a microcontroller 30 that controls the security functions of a vehicle. In addition to the microcontroller, the depicted system optionally includes subsystems such as a power door-lock 31, a starter interrupt 32, a light emitting diode (LED) 33, a siren 34, a vehicle light signaling control 35, and an auxiliary output 36. All these subsystems are controlled by the microcontroller 30 for facilitating all the control and status, indicating purposes involved in the security functional operations of the system.
For example, the LED 33 is typically a subsystem installed on the dashboard to display different lighting patterns indicating to the user (the driver of the vehicle) information concerning the security system status. Additionally, if a security violation event is triggered from outside the vehicle after the security system is armed, the siren control 34 and vehicle light signaling control 35 can be activated in different sounding schemes and head/signal light lighting patterns respectively. These sound and light signals warn about the attempted or achieved intrusion into the guarded vehicle. Further, the auxiliary output 36 can be used to initiate, for example, a radio transmitting device on board the vehicle which can send predefined signal patterns for use in determining the location of the vehicle.
The system outlined in the block diagram of FIG. 1 further includes an ignition switch status indicator 21, a valet/override switch 22, a DIP switch array 23 and a radio receiver 10. The ignition switch status relayed from the indicator 21 is used by the microcontroller 30 to determine the operating state of the entire security system. For example, if the ignition switch of the vehicle is in the normal ON position, and the vehicle is coasting along a road, the security system ignores some of its sensing inputs such as the vehicle body vibrating sensor input.
The radio receiver 10 is used as part of a wireless link, which carries vehicle operator instructions to the vehicle security system. On most occasions, the wireless link is established via electromagnetic signals transmitted from a radio transmitter 12 included in a remote control unit of the vehicle security system. The owner of the vehicle normally carries this remote control unit with, for example, a main ignition switch key of the vehicle.
The DIP switch array 23 in FIG. 1, serves to provide means to program the security functions for the vehicle. One of the conventional programming methods employed for setting up functions provided by a vehicle security system includes setting the ON/OFF states of switches in such a DIP switch array. This DIP switch array is normally installed on the electronic printed circuit board (PCB) of the security device. The block diagram of FIG. 1 schematically illustrates one such system employing this programming scheme. Physical access to the system circuit module is necessary when the vehicle security installed. Physical access to the DIP switch array is also necessary for each subsequent function adjustment or security device reprogramming. The security system module need be removed from the vehicle in order to gain access to the DIP switch array. The circuit module must also be opened to expose the DIP switches to a service technician, or the user, to perform the function adjustment and/or the reprogramming.
Since vehicle security systems are designed to provide ever more complicated functions, using DIP switches to set up some, if not all, of these security functions has become a task that cannot be considered easy or straightforward. Adjustment setting in a large array of DIP switches is not an easy task, because each individual switch has to be identified before a setting can be made. Such jobs normally have to be performed by trained service personnel.
If DIP switches are to be used for function setting in security systems with complicated functions, a large number of DIP switches must be used. As a result, system PCB""s have to provide a significant amount of valuable board space for these DIP switches. The cost of this increased PCB size and the cost of the DIP switches increase the costs of the vehicle security system hardware.
FIG. 2 illustrates a conventional vehicle security system in which a limited number of programming control switches and a wireless transmission are used for programming the security functions. This approach is used to employ the smallest possible number of electrical switches for security system function adjustment and/or reprogramming. It is used in conjunction with a step-by-step procedure. This method is designed to circumvent the necessity of using a large array of switches for the setting of every individual function provided by the vehicle security device.
Normally, by setting the vehicle security system of FIG. 2 to its program mode by properly setting the program switch 24, a user can program all the functions by pressing a small number of control switches on a remote control unit. The remote control unit used for such programming is frequently the unit used for the normal operation of the security system. The design of the entire vehicle security system allows the normal remote control unit to become the programming unit automatically when the system module is set to the program mode.
FIG. 3 shows an example of a conventional arrangement for implementing a programming scheme that includes the use of a external computer. The system illustrated in the block diagram of FIG. 3 incorporates a host computer system 37 that serves to control the function-programming procedure in a security system via the wired interface 25. Although this scheme provides better flexibility in the process of function selection and setting, a direct wired connection of the circuit module to the host computer is necessary. Before the connection to the host computer is made, the circuit module of the vehicle security system has to be removed from the vehicle and taken to the location where the host computer resides. On most occasions, only vehicle service shops have the necessary interface between the host computer and the vehicle security system. As a result, the convenience of programming interface is not directly accessible to the end user, that is, the owner of the vehicle.
An embodiment of the present invention provides a method and system for programming a base unit set with a remote programmer by downloading at least one user selectable command string from a remote programmer to the base unit via a wireless link, where the remote programmer comprises a remote controller, a memory capable of storing a representation of said at least one user selectable command string; user operable switches that can be used to modify the numeric values stored in the memory; a display, and transmitter that can transmit the command string to the base unit; and
a base controller comprising: a microcontroller; and a command memory that holds instructions that cause the controller to determine whether or not a function-programming request code is received, store the user selectable command string in a non-volatile memory, and if the controller is not in the process of function-programming, to determine whether a security event has occurred, and if so, initiate an alarm function.